Summary of computer applications technology (CAT) matric

CAT Final examination notes


System Technologies
Type of Mobile Devices Description
Laptops/Notebooks  Use smaller parts for lower
 A computer that is portable power consumption
 Has a screen size larger than  Runs on battery power
12” or 13”  More expensive than desktop
computers with the same
specs
 Portable
 No wires needed
Tablets  Ideal for quick, small scaling
 A portable computer that has a computing
touch screen  Longer battery life than
 Have bigger screens than laptops and smartphones
smartphones but smaller ones  Don’t have the ability to make
than laptops phone calls or send messages
 Use special operating systems
designed for mobile devices
 Have wireless (Wi-Fi) and
cellular data connectivity (3G
and 4G/LTE)
 Great for reading and watching
videos
Smartphones  Combines features and
 A mobile device which includes technologies of many separate
an operating system and the devices
ability to run and install other  Has a touchscreen
programs  Has a mobile operating system
 Any device smaller than 5” (Google Android, IOS)
Phablets  Midway in size between a
 A smartphone with a screen smartphone and a tablet
size between 5” and 7”  Has the almost usefully larger
screen size of a tablet but
keeps the ability to make
phone calls.

,Single-board computer  Raspberry PI is a low cost,
 A complete computer built on credit-card sized computer
a single circuit board, with that plugs into a computer
microprocessor, memory, monitor or TV, and uses a
input and output and other standard keyboard and mouse
features required of a  Purposes: learning how to
functional computer program, building a media
 Example – Raspberry PI and player, surfing the web
Arduino


The main components of a computer system
 input devices
 processing devices
 output devices
 memory (storage) devices.

 CPU (processing device)
 Central Processing Unit
 The CPU does all the processing that takes place in a
computing device and is responsible for performing
calculations
 Its speed is measured in GHz.
 Examples of brand name - AMD; Intel
 Examples of Model – Intel i7
 Most important component of the computer




 CPU Properties

,  The Speed (measured in GHz)
 The higher the speed of the CPU, the faster it will
perform.
 The number of Cores
 More Cores can make the computer perform better,
especially when running multiple tasks. (More than
one physical processor can be included in a single
chip dual-core = 2 cores, quad-core = 4 cores, hexa-
core = 6 cores and octa-core = 8 cores)
 Cache Size
 the larger the cache memory on the CPU, the faster
the CPU will perform, as the cache memory can then
contain more data.
 RAM (processing device)
 Random Access Memory
 The function of the Ram is to temporarily store the files
you are working on.
 It is where the CPU goes to fetch the instructions and data
that it needs to work on.
 It is volatile memory (meaning it is a computer memory
that requires power to maintain the stored information.)
 Different types of RAM – DRAM (Dynamic RAM), SRAM
(Static RAM), SDRAM (Synchronous Dynamic RAM),
DDRRAM (Double Date Rate synchronise RAM)
 Your computer is starting to become slow, which part of
the computer needs to be upgraded to fix this issue

, Graphics card and GPU
 A graphics card is the printed circuit board that controls
the output to a display screen.
 The graphics card is the hardware as a whole, while the
GPU is a chip, part of the graphics card or an onboard
similar, which stands for "Graphics Processing Unit"
 The GPU is responsible for processing the instructions
that create the pictures on your screen
 There are two types of graphics cards:


Integrated graphics card Dedicated graphics card
They are built into the They are an add-in
motherboard graphics card that is
installed on the
motherboard as an extra
component
Has its own source of Uses the systems memory
memory
Very expensive Inexpensive
Generates a lot of heat Doesn’t generate a lot of
heat
Will deliver better graphics Delivers average graphics
performance
Can be personalized Can’t be personalized

, ROM
 Read only memory
 ROM is used to permanently store instructions that tell
the computer how to start up as well as stores the
motherboards operating software, called the BIOS
 Non-volatile memory
 Stores the computers BIOS (Basic input/output system)
 Different types of ROM – PROM (Programmable read only
memory), EPROM (Erasable and Programmable read only
memory), EEPROM (Electrically Erasable and
Programmable read only memory)




 Motherboard
 A computer motherboard is a large, printed circuit board
that physically connects all the different components of
the computer.
 The main functions:
 To provide a place for other devices or interfaces to
be connected.
 To distribute power to the various components
 To act as a communication hub as the components
send and receive information through the
motherboard

, Hardware and Software
 Hardware:
 Hardware consists of the physical components of a
computer, also referred to as the equipment of a
computer.
 The common physical components of a computer system
are input (keyboard, mouse), storage (hard drive),
memory (RAM), processing (CPU), output (monitor,
printer) and communication (Network Interface Card,
NIC).
 Software:
 the computer programs which provide the step-by-step
instructions to complete the task.
 The two types of software are:
 System software (including the operating system)
 Application software

 System Software
 System software is the specific type software that
manages the computer and is designed to provide a
platform for other software.
 This includes the operating system and other software
that controls and manages the operations of the
computer.

,  The operating system (OS) is the most important type of
system software as it manages all the other programs in
the computer.
 System software is comprised of the:
 Operating system
 Utility programmes
 Device drivers
 It manages the computer in the following ways:
 It translates the instructions from the software to a
language that the hardware can understand
 It sends these instructions to the correct hardware
 It allows different applications to speak to each
other
 It makes sure all the hardware and software on the
computer are in good condition

 Device Driver
 Device drivers are a group of programs that allow the
hardware and the operating system to communicate with
each other.
 A device driver is software that contains a set of
instructions that command a computer’s operating
system on how to communicate with the hardware so
that it can function properly.
 Your OS will use a device’s driver to communicate with
the device.
 Device drivers allow communication between the
operating system and all the devices, such as the mouse,
keyboard, printer, etc.
 The main function of the device driver it to help the OS
understand the information you give it through an input
device or translate the information the computer sends to

, an output device so that it can display the information
correctly.




 Basic system requirements (Software)
 System requirements are the required specifications a
device must have in order to use certain hardware or
software.
 In order to determine which software would work best for
your computer, you will need to look at the system
requirements of the software. The system
requirements refer to a list of hardware and software
requirements that the software will need in order to
function. The list will normally include the minimum (the
lowest specifications needed to let the program work)
and recommended (the specifications where the program
should function best) hardware requirements for the
software.
 This includes the following:
 The amount of hard-drive space needed to install
the software

,  The amount of RAM needed for the software to
function normally
 The GPU and CPU required to do calculations
 The type of programs (usually the type of operating
system) that is required for the new program to
function
 The input and output devices needed for the data to
be collected and displayed

 Minimum vs recommended requirements
 minimum requirement will let you run the game but it
would not look good and may have a lot of slow down
depending on what is going on in the game. if you meet
the recommended requirements then you would be able
to run the game with all the eye candy at a smooth speed
depending on what is going on in the game.


 Application Software
 Application software is software that performs specific
tasks for an end-user
 Advantages:
 They meet the exact needs of the user
 The updated versions of the software are available
regularly
 Disadvantages:
 Developing application software takes a lot of time
 Some software that are designed specifically for a
certain business, may not be compatible with other
general software.
 The application software that is designed to meet
for a specific purpose will be costly for the
developers to develop.

,  Web-based applications
 Web-based application software is application software
that you use over the internet with a web browser.
 Advantages:
 You can use the software from any computer or
mobile device anywhere in the world, as long as you
have an internet connection.
 The software is always up to date
 You don’t have to download or install the software,
which saves storage space.
 Compatibility issues are also not really a problem, as
the software is not being installed and run on the
local device or computer.
 Many of the online apps also provide some free
online storage space
 Disadvantages:
 You cannot use the software if you don’t have an
internet connection